[Apoptosis and caspase-3 in the model of rat silicosis].

OBJECTIVE

To explore the changes of apoptosis of cells in the lung tissue of rats with silica instillation and to its significance in silicosis, and to clarify the role of caspase-3 in the apoptosis progress.

METHODS

Forty-eight rats were randomly divided into saline control groups and silica instillation groups, and the silicosis model was established in rats. Flow cytometry was used for detecting the rate of apoptosis at various stages. Immunohistochemistry for the expression of cleaved caspase-3.

RESULTS

The model of rat silicosis was established successfully. The apoptosis rate in the experimental group was significantly higher than that in the control group, and was increased with time. Caspase-3 was mainly expressed in alveolar epithelium cells, pulmonary macrophages and infiltrated inflammation cells. The expression of caspase-3 in the experimental group was stronger than that in the control group, but its expression intensity was not related to the cell apoptosis (r = 0.215, P > 0.05).

CONCLUSION

The apoptosis of the lung cells plays an important role during rat silicosis genesis. Caspase-3 plays an important role in regulating cell apoptosis during rat silicosis genesis.